Heartworms

Heartworms are round worms that infect our small animals, as well as some marine mammals, foxes and wolves. These nasty little worms, genus species Dirofilaria immitis, spend the adult part of their life in the heart and the bodies larger blood vessels. This causes significant mechanical damage to the valves and structural integrity of the heart and vessels which can ultimately cause a mortality event in our pets.

Our pets become infected by heartworm larvae that are transmitted by mosquitoes. The larvae circulate in the bloodstream feeding and enlarging in size until they land in the heart and reach adult status. At adult status these monsters from within can reach up to 15 inches in length. One can imagine that having these critters within the chambers of a heart isn't conducive to proper function and thus our pets will show signs of heart failure or caval syndrome. Unfortunately, if your pet starts to illicit clinical signs of heart failure they usually have very progressed disease. However, the initial clinical signs shown by infected patients will be decreased activity and appetite, weight loss, and coughing.

Once you find these clinical signs it is important to rule out heart worm if you have traveled through an area know to have heartworm. Specifically on our coast of central Oregon heartworm infections are extremely rare but that doesn't mean impossible. If the history and clinical match for possible heartworm infection your veterinarian will likely perform a blood test for the heartworm while also taking x-rays of the chest and possibly a cardiac ultrasound.

How do you and your veterinarian prevent such an infection? There are many heartworm preventatives on the market, some better then others. These preventatives should be taken year round if our pets are traveling at any point to areas of possible infection. Here on the central coast, if our patients only live and stay here it isn't necessarily recommended to treat year round but the cost to benefit is such that it would be a decent idea to give a preventative regularly. Specifically out here we treat a lot fleas and ticks on a regular basis, Revolution is a product most are familiar with to prevent fleas and ticks but it also acts as a preventative for heartworm.

If your pet has traveled to areas outside of the central Oregon coast and wasn't on heartworm preventatives prior to traveling, it is imperative to check for heartworm infection prior to re-starting heartworm preventatives. The problem is that the preventatives and the actual adulticides that kills already established infections are different. If a patient that has a heartworm infection is given preventatives at home, the patient is at risk for severe anaphylaxis and possible life threatening situations. Thus, it would always be recommended to be on heartworm preventatives prior to travel, and if not to be tested upon return.

If your pet is infected with heartworm it is imperative to undergo treatment for the infection under direct supervision of a veterinarian and not to do it at home for a myriad of reasons. If you have questions regarding this subject please feel free to call or email us here at Animal Medical Care of Newport.


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